All alone

Do polar bears get lonely? I’m not being flippant, just attempting to find out why animals such as humans or penguins are gregarious while others, such as polar bears and eagles, live more solitary lives.

Frank Anders, Amsterdam, The Netherlands

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Jon Richfield, Somerset West, South Africa

Having a gregarious or solitary nature are species-specific survival strategies adopted by different animals and birds. Big predatory mammals such as polar bears, grizzlies and tigers isolate themselves from one another to avoid competition with other members of their own species. By spreading out, they also expand their feeding grounds and breeding territories. If fellow species members come into close proximity there can be fierce competition for food, mates and territory. The same is true with many solitary species of birds, such as eagles and condors.

These animals and birds usually pair up during the breeding season to reproduce, and separate soon after successful mating or when they have raised their young ones. In most cases, raising the young is the sole responsibility of females. Indeed, males of such species sometimes kill their young to increase their own reproductive success.

Social animals, by contrast, find strength in numbers. Animals such as antelope on the African savannah or penguins in the Antarctic form big colonies, where they huddle together for warmth and to alert each other to a potential predator attack. In a large herd or colony, losses to predators are negligible compared with what they would be if the animals were in isolated groups.

Between the solitary and social extremes are creatures like lions, wild dogs and wolves, which often hunt in groups and display differing degrees of social interaction and cooperation.

A similar question can be asked about why some plants are gregarious while others are solitary. In one intriguing strategy, called allelopathy, gregarious plants secrete chemicals into the soil to reduce competition from related species that cannot survive the presence of these compounds. As with animals, these strategies have evolved to maximise the plants’ chances of survival.

Saikat Basu, Lethbridge, Alberta, Canada

Bears and eagles rarely associate with their own kind because individuals need to defend their own feeding territories in which food is often scarce. Polar bears live in an environment where the food resources are too limited to sustain a large community, so it makes sense for them to be the only predator in this particular niche. When food is plentiful both bears and eagles will gather together with a reasonable degree of amity.

The reverse is true for social animals, including humans. Social animals are often prey for other species, and cluster together for safety against predation though this is only one of the reasons for group formation. But when food is scarce, individuals may break away from the group to find it.

Whether an animal can feel anything resembling the loneliness humans feel is hard to say. However, highly social animals such as certain types of parrots seem to be adversely affected when kept alone. Some parrots will engage in bizarre behaviours and can self-mutilate. Some large parrots will even seem to go “insane” if subjected to long periods of isolation.

On the other hand, certain animals that are by nature solitary hardly seem to be affected at all. Some fish, in particular some types of cichlids, will fight viciously with their own kind if more than one is kept in an aquarium. Guam rails, a kind of flightless bird, are notoriously intolerant of their own kind, which has obviously made breeding them in captivity very difficult.

So the answer to the question is a qualified yes some animals will feel “lonely” if they are by nature highly social. However, some will only engage with their own at specific times and in a highly ritualistic fashion, such as when mating or defending their territory.

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It depends on the bear and the circumstances. Loneliness is a reaction to deprivation of company when company is appropriate. In the case of polar bears, company usually represents competition or threat, so they do very well by themselves, thank you unless you happen to be small enough to eat. In certain situations, when food and breeding are not relevant, males will wrestle harmlessly to establish dominance, thereby reducing the risks of dangerous fighting when mating time comes, but that is pretty much that.

Cubs want their mother’s company for food, protection and reassurance, and they want each other’s company for socialisation, warmth and play. Females want the company of their cubs, but keep other adults (and cubs) at a distance. Once her cubs mature or die, a mother again becomes a loner until mating time, and then tolerates males only briefly. She has no reason to want any company beyond that.

It is all part of the adaptation to their environment. In zoos, where security and food are no constraint, polar bears often seem happy to have the stimulus of company.

Jon Richfield, Somerset West, South Africa

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